Experimental support for Russell (coercions moving inside lambda & pattern

[helm.git] / helm / software / components / ng_refiner / nCicUnification.ml

diff --git a/helm/software/components/ng_refiner/nCicUnification.ml b/helm/software/components/ng_refiner/nCicUnification.ml
index 805ea859f8beef8be33eb03d123b850f37a5c48e..e521dd30144f7db95de3950996dd1c09cd8b54ac 100644 (file)
--- a/helm/software/components/ng_refiner/nCicUnification.ml
+++ b/helm/software/components/ng_refiner/nCicUnification.ml
@@ -50,7 +50,7 @@ let eta_reduce subst t =
           let _,_,t,_ = NCicUtils.lookup_subst i subst in
           let t = NCicSubstitution.subst_meta lc t in
           eat_lambdas ctx t
-        with Not_found -> ctx, t)
+        with NCicUtils.Subst_not_found _ -> ctx, t)
     | t -> ctx, t
   in
   let context_body = eat_lambdas [] t in
@@ -241,9 +241,11 @@ let tipify exc metasenv subst context t ty =
         if is_type attrs then
          metasenv,subst,true
         else
+         let _,cc,ty = NCicUtils.lookup_meta n metasenv in
+         let metasenv,subst,ty = sortfy exc metasenv subst cc ty in
          let metasenv = 
            NCicUntrusted.replace_in_metasenv n
-            (fun attrs,cc,ty -> NCicUntrusted.set_kind `IsType attrs, cc, ty)
+            (fun attrs,cc,_ -> NCicUntrusted.set_kind `IsType attrs, cc, ty)
             metasenv 
          in
           metasenv,subst,false
@@ -253,9 +255,11 @@ let tipify exc metasenv subst context t ty =
          if is_type attrs then
           metasenv,subst,true
          else
+          let _,cc,_,ty = NCicUtils.lookup_subst n subst in
+          let metasenv,subst,ty = sortfy exc metasenv subst cc ty in
           let subst = 
             NCicUntrusted.replace_in_subst n
-             (fun attrs,cc,bo,ty->NCicUntrusted.set_kind `IsType attrs,cc,bo,ty)
+              (fun attrs,cc,bo,_->NCicUntrusted.set_kind `IsType attrs,cc,bo,ty)
              subst 
           in
            optimize_meta metasenv subst (NCicSubstitution.subst_meta lc bo))
@@ -354,8 +358,8 @@ let rec instantiate rdb test_eq_only metasenv subst context n lc t swap =
        | _ -> assert false)
   | `IsType
   | `IsTerm ->
-     (match ty,t with
-         NCic.Implicit (`Typeof _), _ ->
+     (match ty with
+         NCic.Implicit (`Typeof _) ->
           let (metasenv, subst), ty_t = 
             try 
               NCicMetaSubst.delift 
@@ -375,7 +379,7 @@ let rec instantiate rdb test_eq_only metasenv subst context n lc t swap =
           in
            delift_to_subst test_eq_only n lc (attrs,cc,ty_t) t context metasenv
             subst 
-       | _, _ ->
+       | _ ->
         let lty = NCicSubstitution.subst_meta lc ty in
         pp (lazy ("On the types: " ^
           ppterm ~metasenv ~subst ~context lty ^ "=<=" ^
@@ -546,6 +550,15 @@ and unify rdb test_eq_only metasenv subst context t1 t2 swap =
        | NCic.Appl (NCic.Meta (i,_)::_), _ when List.mem_assoc i subst ->
             unify rdb test_eq_only metasenv subst context t2 t1 (not swap)
 
+       | C.Meta (n,_), C.Meta (m,lc') when 
+           let _,cc1,_ = NCicUtils.lookup_meta n metasenv in
+           let _,cc2,_ = NCicUtils.lookup_meta m metasenv in
+            (n < m && cc1 = cc2) ||
+             let len1 = List.length cc1 in
+             let len2 = List.length cc2 in
+              len2 < len1 && cc2 = fst (HExtlib.split_nth len2 cc1) ->
+          instantiate rdb test_eq_only metasenv subst context m lc'
+            (NCicReduction.head_beta_reduce ~subst t1) (not swap)
        | C.Meta (n,lc), t -> 
           instantiate rdb test_eq_only metasenv subst context n lc 
             (NCicReduction.head_beta_reduce ~subst t) swap
@@ -559,12 +572,8 @@ and unify rdb test_eq_only metasenv subst context t1 t2 swap =
              (NCicTypeChecker.typeof ~metasenv ~subst context meta)
           in
           let metasenv, subst = 
-           try
-            unify rdb test_eq_only metasenv subst context 
-              (C.Meta (i,l)) lambda_Mj swap
-           with UnificationFailure msg | Uncertain msg when not norm2->
-            (* failure: let's try again argument vs argument *)
-            raise (KeepReducing msg)
+           unify rdb test_eq_only metasenv subst context 
+            (C.Meta (i,l)) lambda_Mj swap
           in
           let metasenv, subst = 
             unify rdb test_eq_only metasenv subst context t1 t2 swap
@@ -599,14 +608,12 @@ and unify rdb test_eq_only metasenv subst context t1 t2 swap =
              with
                 Invalid_argument _ -> 
                  raise (Uncertain (mk_msg metasenv subst context t1 t2))
-              | UnificationFailure _ | Uncertain _ when not (norm1 && norm2) ->
-                 raise (KeepReducing (mk_msg metasenv subst context t1 t2))
               | KeepReducing _ | KeepReducingThis _ -> assert false
            in 
              metasenv, subst
 
        | (C.Match (Ref.Ref (_,Ref.Ind (_,tyno,_)) as ref1,outtype1,term1,pl1),
-          C.Match (ref2,outtype2,term2,pl2)) ->
+          C.Match (ref2,outtype2,term2,pl2)) when Ref.eq ref1 ref2 ->
            let _,_,itl,_,_ = NCicEnvironment.get_checked_indtys ref1 in
            let _,_,ty,_ = List.nth itl tyno in
            let rec remove_prods ~subst context ty = 
@@ -622,9 +629,9 @@ and unify rdb test_eq_only metasenv subst context t1 t2 swap =
              | C.Sort C.Prop -> true
              | _ -> false 
            in
-           if not (Ref.eq ref1 ref2) then 
+           (* if not (Ref.eq ref1 ref2) then 
              raise (Uncertain (mk_msg metasenv subst context t1 t2))
-           else
+           else*)
              let metasenv, subst = 
               unify rdb test_eq_only metasenv subst context outtype1 outtype2 swap in
              let metasenv, subst = 
@@ -647,6 +654,12 @@ and unify rdb test_eq_only metasenv subst context t1 t2 swap =
        | _ -> raise (KeepReducing (mk_msg metasenv subst context t1 t2))
      (*D*)  in outside None; rc with exn -> outside (Some exn); raise exn 
     in
+    let fo_unif test_eq_only metasenv subst (norm1,t1 as nt1) (norm2,t2 as nt2)=
+     try fo_unif test_eq_only metasenv subst nt1 nt2
+     with
+      UnificationFailure _ | Uncertain _ when not norm1 || not norm2 ->
+       raise (KeepReducing (mk_msg metasenv subst context t1 t2))
+    in
     let try_hints metasenv subst (_,t1 as mt1) (_,t2 as mt2) (* exc*) =
     (*D*) inside 'H'; try let rc =  
      pp(lazy ("\nProblema:\n" ^